Technical Field
Certain embodiments of the invention relate to a Stirling cryocooler, and particularly, to an expander of a Stirling cryocooler.
Description of Related Art
A displacer is provided in an expander of a Stirling cryocooler. One end of the displacer is disposed on a “low temperature” portion of the expander, and the other end is disposed on a “normal temperature” portion thereof. Accordingly, a temperature gradient is produced in the displacer when the cryocooler is used. Consequently, via the displacer heat from the normal temperature portion invades the low temperature portion. Heat having intruded this way decreases the refrigerating capacity of the Stirling cryocooler.